No free play on the clutch

[Vikas]

2000 Nissan Maxima

I just had slave cylinder and hoses replaced. Now the clutch pedal is really stiff and engages at the top of the travel and there is no free play left at all. The clutch pedal rests about inch higher than the brake pedal and all the engagement seems to be happening in the top inch of the pedal travel. I am not sure what could have gone wrong. Master was not touched during this repair but might have ran out of all the fluid during the swapping of slave cylinder and hoses. It was bled using two person method. The pedal is not soggy at all but rather lot stiffer than it was before. The problem is that engagement point is very high.

Any idea as to what could be the culprit? I am taking back to the mechanic on Monday. He suggested I drive for a while to see if it self-adjusts but I do not see how that would work.

I searched and did not find any topic with zero free play. On the contrary, there are bunch of people who were complaining about too much free play. There are also contradiction opinions on whether the master cylinder rod should be adjusted or not.

Please help!

 

[Dakota1820]

could it just be a side effect of aftermarket parts. i had a mazda like that kinda a pain but i did get used to it

 

[DrDusty86]

In my experience, it needs to be bleed when it does that, Dot 3 brake fluid.....My ranger did that once, I bleed it, it was fine for 272k miles more until I sold the truck on the factory clutch.
Dusty

 

[Towncivilian]

You can adjust the clutch pedal. See CL-6 of the factory service manual if you haven't yet. Bleeding instructions also begin on the same page.

 

[Vikas]

It was bled. Unfortunately, I had to leave the vehicle there, so I was not the one pumping the pedal down! I looked under the clutch and looks like the rod can be turned in and there is a lot of travel available there i.e. it is almost all the way out at the "wrong" end.

But what I am afraid that if the slave cylinder rod is longer than the OEM, the fork would remain under constant pressure even after I adjust the free play at the pedal via master cylinder rod. Is that correct assumption or am I worrying too much? Is the

How do I verify that I will have free play at the clutch fork? The factory service manual says nothing about any adjustment at the slave cylinder or at the fork. How critical is the length of the slave cylinder rod in the scheme of the things?

 

[yonyon]

Originally Posted By: Vikas

How do I verify that I will have free play at the clutch fork? The factory service manual says nothing about any adjustment at the slave cylinder or at the fork. How critical is the length of the slave cylinder rod in the scheme of the things?


You need to have non-zero freeplay. This is pretty much a universal truth. If freeplay at the slave is zero then you've got preload and the release bearing is doomed! Doomed, I say! DOOMED!

/doom
//doom
///doomey-doom

 

[yonyon]

Also: every time I've encountered this sort of thing it was because the parts guy was apathetic and didn't bother to look up the parts properly. Always look up clutch parts yourself or have them looked up by a parts guy who's over 40 years old and has seen your gun collection. If you don't have a gun collection you pretty much have to look up the parts yourself.

 

[demarpaint]

Originally Posted By: yonyon
Originally Posted By: Vikas

How do I verify that I will have free play at the clutch fork? The factory service manual says nothing about any adjustment at the slave cylinder or at the fork. How critical is the length of the slave cylinder rod in the scheme of the things?


You need to have non-zero freeplay. This is pretty much a universal truth. If freeplay at the slave is zero then you've got preload and the release bearing is doomed! Doomed, I say! DOOMED!

/doom
//doom
///doomey-doom


+1 There's a very strong possibility the clutch was bled wrong. IIRC some have to be reverse bled when you change the slave cylinder.

 

[Vikas]

Is there a chance that by adjusting the pedal rod length, there will be free play at the slave also? I almost feel like I should intentionally put the air in the system to see if I can get free play at the slave! OK, I am only kidding :-(

Please explain how wrong bleeding can lead to this condition. I would think if there is air in the system, I will have trouble pushing the clutch all the way in rather than losing the free play. Are you thinking that somehow too much fluid has gone in the system? Is that even possible without (massive) pressure bleeding the system?

I still need to know how to determine the free play at slave? Feel the fork and the slave and see if the rod can be wiggled when the pedal is up?

 

[yonyon]

It won't wiggle much, but enough that you know it's not loaded.

 

[Scott_Tucker]

This is definitely an install issue. The shop needs to recheck it's work. This car should have never left like this. Air in the system would not cause this. It is either the wrong part or the master cylinder push rod is mis-adjusted.

 

[SteveSRT8]

I cannot believe that someone didn't test drive this first and notice!

 

[mechtech2]

Zero freeplay [or even preload]at the clutch pedal /rod/ master cyl wont cause the TB to stay in pressurized contact. The hydraulic adjustment will compensate aut omatically.
And remember, the TB is SUPPOSED to ride with zero freeplay - it is in constant contact on most cars with hydraulic clutches.

My advice is zero or a hair more clearance.

 

[Scott_Tucker]

Actually, the piston can bottom out and, if the pushrod adjustment is too long, hold the clutch fork against the bearing - which can wear it out prematurely or cause it to overheat. I don't think they are in constant contact. If they are, the load is very light.

 

[Vikas]

I did not drive the car on Sunday. Monday morning I gather the 12mm wrench and pliers to adjust the free play at the pedal. When I moved the car in to garage, I noticed that the clutch had correct free play and pedal was not stiff to push. There was no loss of fluid either. I had no idea how it could have fixed itself.

I drove to the shop as I have to get the leaky axle seal replaced. By the time I reached the shop (about 5 miles of back roads and few stop signs), the there was no free play and the clutch pedal was hard to push.

I am concerned about the inconsistency of the pedal feel. Anyway, the mechanic adjusted the master cylinder rod at the pedal to give me free play. I will watch how it behaves for next couple of days. I wonder if it needs to be bleed again.

 

[ltslimjim]

I had a bit of a similar problem myself recently, the clutch pedal would bleed down over night(lose pedal) and I'd have to pump it up in the morning. The seals in the slave cylinder wound up being the culprit, but I had only replaced the master initially(due to visible leak pedal side).

Replacing the slave the other week, after not doing them both together, has solved the leak down over night. However, I also have a few thousand miles in on the new clutch, so the adjustment at the pedal should at least be checked again.

So, you may have a system that is bleeding down slightly and thus the 'free play' after not driving. Just a hunch...

 

[mechtech2]

Originally Posted By: Scott_Tucker
Actually, the piston can bottom out and, if the pushrod adjustment is too long, hold the clutch fork against the bearing - which can wear it out prematurely or cause it to overheat. I don't think they are in constant contact. If they are, the load is very light.


It would be the opposite of what you say.
The clutch may not go all the way if the pushrod is too long - there will be LESS total travel.
And I know the TB is in constant contact - a floating contact.
It is better than accelerating it from zero to full speed.